I'm hooking up a air/fuel ratio meter to my Fiero to further investigate the lean condition caused by no EGR.

What connector is the wire located? What color is it? As I read it, it is purple,
but which purple one? What pin?

looks more like pink to me!

I want to connect it near the ECM so it is not in the engine compartment!

This was easy in my Honda! The wires actualy look differant colors!

What engine and year?

V6 is Purple to D7.

I thought so! I ended up finding it on a web site fiero tech or something like that! The manuals I have Chiltons and Haynes had me screwed up they said it was C2 (black/blue) plug in reality it was the grey/black, or as I figured it out terminal D7 on the 16 pin plug! Thanks Terry for always being willing to help! I and the rest of the forum opreciate it!

Anytime! I appreciate the comment.

So I'm curious how you are equating no EGR to a lean condition.

Are you getting an error code?

Terry

[This message has been edited by terryk (edited 06-29-2000).]

Well, people have claimed that by takeing off the EGR valve and related components that it leads to a lean condition causeing burnt pistons. As I understand it it is more of a timeing advancement during EGR operation.

I'm hooking up the A/R meter to see for my self and to relay my findings to the Fiero Forum to (finaly solve) or at least give more answer to the debate!

Fierocious,

The advance is increased up to 10 degrees extra during EGR, but unless it is pinging causing a problem, I doubt a piston will get burnt. Power enrichment is enabled at 3600 RPM and 12% TPS (or a 9% change) and the AFR jumps to 12:1. At that point the it's rich enough to cool the cyliner and before that the load is low.

My concern with no EGR is the part throttle pinging problem.

I doubt the AFR meter will tell you enough to draw any useful conclusions. but please, let me know what you find.

Terry

[This message has been edited by terryk (edited 06-29-2000).]

Will do! I also want to play with fuel pressure and the air temp sensor (variable resistor) to see if in fact there is some tuneability within the system. I have a 95 Civic and it is belived that there is no tuneing to be done without the computer, I found differantly if you increase the fuel pressure 5psi and up the timeing 2 degrees it gives about 2 tenths on a stock and about a half a second on a car equiped with intake and exaust mods. While it's not a neck snaping differance it's enough to get ahead of the other guy.

I still would like to know why Fieros burn pistons or if this falls under all fieros start on fire.

Don't crank the pressure up too much as the injectors will start to spit.
Fiero V6's don't burn pistons as a general rule. I think the comment is
based on the fact that running the engine too lean will burn valves or
pistons, but it's certainly not a "Fiero" thing.

Try grounding D8 (Dark Green). I don't know if the ECM looks for that line
being open with no EGR request or and grounded with an EGR request. It might
still throw the code, but give it a try.

Solenoid.

The Fiero V6 ECM's are called "C3". The ALDL rate is one stream each 1.25
seconds (160 baud). I have run a couple of Fiero's on a P4 which is 8192
baud. The one I've found that works the best so far is the 1227749 from a
Syclone/Typhoon truck, 87-88 Sunbird GT Turbo or a 87-88 Quad 4.

I used the Sunbird Turbo code, changed it back to a 1 BAR map, the number of
cylinders, fuel, spark etc. The Sylcone code is a problem since the fueling
and spark is set for the turbo and the 4.3L displacement. You wind up making
as many changes. Another problem limiting the number of ECM choices is the
HEI distributor. There are other ECM's for the 2.8L/3.1L engines but they
are DIS and running DIS code on an HEI just taken more changes to the code.

Well, there is one other option and that's the 1227730 or 1227727 ECM and 90
Camaro V6 code. HEI, MAP, etc. That is a good option too. It would likely
need some additional tweaking to drag the INT and BLM (fueling) into range.
The code is also for AL heads, so the spark advance is a bit aggressive.

Finally, none of those ECM's just plug in. You have to do some wiring.

Terry

How do you know all that? That is amazing! How do you go about changing the ECM's program codes? Prom? or do you have to send perameters to the ECM through the adl plug?
I think it's adl? The one ya plug a paper clip in!
So does it make a differance as far as driveability or gas miledge? If it runs faster it can adjust more persicely as I would understand. Right?

We are still working on the mechanicals on Kidzwheelz 4 banger turbo but it is comeing real slow as he is going through a seperation. And he's into his truck at the moment! This will help for that too.

Thanks for the help. Sorry I ask alot of questions.

Ask all you want. How do you think I figured a bunch of this stuff out? You have to dig and work on it.

Let's take this offline for now.

email me at terryk@foothill.net

Terry